Draft-gear.



F. GOURSUN.

DRAFT GEAR. APPLICATIQN'HLBD 111111. 25, 111134 Patented Aug. 12,1913.

TED STATES PATENT orme;

JOHN r. coURsoN, or PITCAIRN, PENNSYLVANIA.

nanna-enen.

Specicatonpg Letters' Patent.

patented alle. i2, isis.

application nea Marcil 25, i913.. serial No. 756,692.

My invention consists of an improvement 1Q in friction draft gears for railwaycars, etc.,

and it has for its object to provide a\dra gear of simple construction and high elli# ciency, designed to utilize the wedging and `spring,

releasing qualities of wedge blocks arranged between a central bufiing member and surrounding friction members, and a pressure within an inclosing casing, and adapted to vtransmit bung and pulling strains to the car underframe.

The particular object of the present invention is to provide, in a friction draft gear of this type, means for exerting frictional resistance between thefrietion members and the casing, by thecoperating action of opposing wedge members adapted to equalize and multiply the strain and to transform it into frictional resistance, evenly throughout the length of the friction-creating members.`

These objects are accomplished, one preferred forni of the apparatus, morlelfully hereinafter described, as illustrated in theI accompanying drawings, in which- Figure 1 is a central vertical sectional view of the complete draft gear assembled,

the parts being shown in extended position,`

the section being indicated by the line I. I. of Fig. 2. Fig. 2 is a horizontal' sectional view of the gear, the section being indicatedl by the line II. II. of Fig. 1. Fig. 3 is a cross sectional View, indicated by the line III; III.

5 casing.

of Fig. 1. Fig. 4 is a similar cross sectional View, showing a modified construction having a plurality of closely assembled friction members engaging receiving grooves in the, Fig. 5 is a perspective detail view of one of the expanding wedge blocks. Fig. 6 is a similar view of -one of the friction shoes. Fig. 7 is a similar View of-one of the friction shoes used in the construction shown o in Fig. 4. Fig. 8 is a detail View showing av modified construction of the inner terminal wedge used with the friction shoes of Figs.

In the drawin a 2 represents the drawbar of a coupler fixe y connected with the yoke 3 by transrerse belts Jin t n rcits `casing or cylinder 5 at top4 and/bottons shown, the yoke and /casingb'ing located bel-tween lthe central/sills 6, 6.

A .bearing block or piece 7 is set against end of which'block bears the rounded end 8 preferably secured to the end of the yoke. The front stops 10 extend inwardly from each sideko'fjhe center sill 6, and sustain the pulling eect of the draft gear and impart it to said sills, lw'glviile similar rear stops'lO act to receive and impart buiiing strains in the same manner. i

'Ihe central ,wedge block'll has angularly disposed wedge faces 12 o-f pyramdal arrangement corresponding in numberv and degree of slope to the expanding wedges 13,

ter at such an angle to the horizontal as to produce a maximum expansion with resulting free release. Wedge block 11 extends outwardly and bears by its main body portion against ont follower plate 14, which plate in turn engages the rear end of drawbar 2 between the arms of yoke 3.

In the construction shown in the upper figures of the drawing, the expanding wedge blocks-13 are provided with outer flat faces which engage the inner,A flat faces of corresponding friction shoes 15, the wedge blocks 13 having at each end inwardly disposed angle to co-act with the faces 12 of the front central wedge 11, and with the faces 'of the inner wedge member 18. y fIhe friction shoes 15, one for each expanding wedge block 13, are cylindrically rounded at their .outer portions, as lat 19, conforming to theinner surface of the casing 5 and adapted "to make frictional engagement therewith. The inner faces 20v of frictionv shoes 15 are substantially parallel with their outer faces and `with the longitudinal center of the gear, the inner portions of the friction shoes being deected inwardly, as shown, providing an inner wedge terminal portion 21, havingl inner wedge faces 22 for co-action with t l'cbrrespondingI wedge faces of the .inner central wedge 18. Said wedge 18 isI providefd'at each end with series of forwardly disposed wedge faces '23 and rearwardly di faces 2t4 respecthely,l adapt to engage wedge. fesse 17' and l922'respectively of the tomary-in this art, said yoke embracing thg,

the rear end of cylinder 5, against the outer .of yoke 3 with an interposed lling block 9,

' said faces tapering inwardly toward the cen-` faces 16 and 17 respectively,` adapted p'osed wedge.

expanding wedge blocks 13 and friction shoes 15, as clearly shown.

A bntling spring 25 of well-known construction and function is interposed between the inner end of cylinder 5 and the rear ends of :friction shoes 15, as clearly shown, the construction in this respect being similar to that shown in my prior Patent, No. 1011034, dated Dec. 5, 1911.

its will be seen from the above description and the drawings, the gear is composed of wedge'blocks and co-acting friction shoes having contracting wedge .faces all of substantially the same angle, having a high degree of expanding power and of sutliciently blunt slope to entirely prevent any tendency to stick in releasing at the termination of bufling or pulling strains.

The engaging faces between the friction shoes 15 and t-he casing, and between the friction shoes and the expanding wedge blocks 18, are substantially parallel with each other and with the axial center of the gear, thus avoiding any bindingtendency, other than that exerted by the action of the main central wedge members 11 and 1S. In iper-ation, either in butling or pulling, these wedges approach each other, due to the movement of the drawbar toward the casing, or vice versa, spring 25 thus being more or less compressed. The initial effect is to separate the expanding wedge blocks 13, which in turn expand the friction slices 15 into binding engagement with the casing, the action being supplemented and largely assisted by the interengagement of friction faces 22 ofthe friction shoes and 2li of the inner wedge 18.

ln compressing the gear, members 15 and 13 will. have a slight longitudinal movement with relation to each other, the parts being maintained in tight-engagement throughout at every stage of the operation, whatever the pressure may be, either in bufng or, pulling. The expanding action of wedges 11'Iand 18 is thus transmitted directly, and through the interposed blocks 13 to the friction shoes 15, equally throughout their length, so that the friction shoes are -thus pressed tightly against the inner surface of the casing to the same degree at all points of their length and circumferential width. Any tendency to tipping or undue strain or unequal pressure at any point is thus completely obviated and eliminated, due principally to the fact that the degree of slope or inclination of the wedge members is lsubstantially the same throughout, and their operation is entirely independent of any supplemental or different wedge faces or members, as in the case of acute angle wedges. The absence of any acute angle wedges also completely obviates and overcomes any tendency to sticking or binding of the' construction, thus insuring free and prompt, release. Due to the anl nordsee rangement of the wedge vmembers and their uniformity and simultaneity of action, a full even bearing of the friction members is prompt-ly exerted and'uniformly maintained under whatever 'pressures may be exerted. The'resulting friction, due to the construction, is also uniformly highy and efficient.

Figs. t, Y and 8 illustrate a modified construction `employing a considerable number of comparatively narrow friction shoe members 15a associated together in an annular series of closely adjacent, somewhat narrow segmental shaped sections, the friction-creating edgesof which are J-shaped,.as indicated at 19B, and interfitting with corre sponding shaped grooves 5 in the cylinder 5. The inner edges 2Oa of the shoes 15a are arranged `in circular form, Vadapted to engage the outer curved faces of the expanding wedge blocks 13". Said wedge blocks are arranged in operative relation to a central expanding wedge member 11""antl an inner wedge member 18a having fact; 12 and 23a respectively, and operable in the same manner as above described. The inner Wedge member 18il is lcylindrical as to its middle body portion and is provided'with an inner cone extension 24a, the faces of which-correspond to the inner wedge portions 211 of the block previously described. The friction shoes 15" are each provided with inwardly extending lip projections 21 having inner flaring wedge faces 22,

adapted to engage the cone 24a and to be actuated thereby. r1`he operation of this conu struction is substantially similar to that using Vthe pyramidal shaped wedge members, the construction providing for a multiplicity of friction surfaces and an increase of their operating area.

1n each construction, it will be observed that, upon bufling pressure being exerted inwardly by the drawbar and front wedge 11, inward vmovement will be imparted to ,the friction shoe members by their inwardly overhanging lips or projections 21 engaging the inner wedge member. Such wedge member thus operates to pull the friction shoes inwardly of the casing by engaging their rfront portions and at the same time forcibly expanding these portions into operative engagement with the casing. The construction in this respect is also highly efficient in immediately causing an `exyninding action throughout all portions of the friction shoes and exerting aninitial inward pulling' or dragging act-ion, in pulling. The inward pressure of spring 25, operating against the inwardly projecting ends .21 of the friction shoes, primarily causes an immediate expansion thereof by action. against the inner wedge member 18, the outer portions of the shoes 15 being also promptly thrust into binding engagement.

Vlhile l. have shown and described the wedge memberbl as of substantially uniform degree, it will be understood that- I do not desire to be limited exactly to these proportions, and that good results may be had by substantially conforming to the. arrangement and design shown.

I am aware that opposing wedge members hare been utilized' between friction blocks having exterior friction surfaces in sliding and frictional engagement with the interior frictional Surface of an inelosing shell or ease, as in the patent of Moore 7.34674. but in such constructions the frietional engagement is directly between the principal wedge blocks and the casing itsel t. ln my construet-ion, the novelty consists in providing` between the wedge members and the eamig. friction shoes having substantially parallel inner and outer faces and lSupplemental inwardly extending wedging terminals eo-aeting with one of such wedge members.

Having described my invention, what l claim is:

1. In a friction draft gea1,the combination with the casing and the relatively movable drawbar, of friction Shoes engaging the easing having inner substantially parallel faces and inwardly extending wedge portions, ay central bulling wedge. bloelt, expanding wedge blocks between the friction shoes and said wedge block. and an inner wedge block having oppositely disposed facel engaging the 'adjacent faces of the expanding wedge blockb` and of the wedge. portions of the friction shoes. Substantially as set forth.

2. v'ln a friction draft gear, the combination with a easing and a relatively movablel dra wbar; of friction shoes engaging the casing having inner Salwtantially parallel faces and inwardly extending wedge portions, a aepamting wedge haring forwardly and rear\\'ardly disposed wedge faces engaging said edge portions by its rearwardly disposed wedge faces, a central batting wedgeI blot-lt, and expanding wedge blocks having faces engaging the friction shoes, bnliing edge block. and the forwardly disposed edge faces of the separating wedge respectively, substantially as set forth.

ln testimony whereof I hereuntoA atiix my signature in the presence of two Witnesses.

JOHN lf. COURSON W it nesees l1. Heen, C. M. CLARKE.

Copies of this patent may be obtainedrfor five cents each, by addressing the Commissioner `of Patents, Washington, D. C. 

